San Diego, California, United States, October 14, 2026
Viking Therapeutics, Inc. has announced the initiation of its Phase 3 clinical development program for oral VK2735, an investigational treatment being developed for obesity and related metabolic disorders. The program, named SUNRISE, includes two randomized clinical trials designed to evaluate the efficacy and safety of a once-daily oral tablet in adults with obesity, including patients with type 2 diabetes. VK2735 is a dual agonist of the glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) receptors, which play important roles in appetite regulation, glucose metabolism and body-weight control. The move into Phase 3 represents a major milestone for Viking as it expands development of VK2735 beyond its injectable formulation. If successful, the oral formulation could provide an additional treatment option for people who prefer tablets over injections. However, VK2735 remains investigational, and its safety and effectiveness have not yet been established for routine clinical use.
SUNRISE Phase 3 Program Evaluates Oral Obesity Treatment
The SUNRISE clinical program consists of two pivotal studies, SUNRISE-1 and SUNRISE-2, designed to assess oral VK2735 in different adult patient populations. Each study aims to enroll approximately 560 participants and will use a randomized, double-blind, placebo-controlled, multicenter design to evaluate treatment outcomes over 68 weeks. SUNRISE-1 will evaluate adults with obesity, defined as a body mass index (BMI) of at least 30 kg/m², or adults who are overweight, with a BMI of at least 27 kg/m², and have at least one weight-related comorbidity. Participants in this study will not have type 2 diabetes. SUNRISE-2 will evaluate adults with overweight or obesity who also have type 2 diabetes, a population in which weight management can be particularly important for overall metabolic health. Participants in both studies will be assigned to receive once-daily oral VK2735 at doses of 27.5 mg, 35 mg or 55 mg, or a matching placebo. The primary endpoint will measure the percentage change in body weight from baseline after 68 weeks of treatment compared with placebo. Secondary and exploratory endpoints will examine additional measures of efficacy and safety, including the proportions of participants achieving at least 5%, 10%, 15% and 20% body-weight reduction. These measures will help investigators assess the extent of weight loss across treatment groups and characterize the candidate’s overall clinical profile.
Dual GLP-1 and GIP Mechanism Targets Metabolic Health
VK2735 is designed to activate both GLP-1 and GIP receptors, which are involved in regulating appetite, food intake, glucose control and metabolic function. GLP-1 receptor activation can reduce appetite and support weight loss, while GIP receptor activation may complement these effects through additional metabolic pathways. By combining activity at both receptors, Viking aims to develop a treatment capable of producing meaningful weight reduction while addressing metabolic factors associated with obesity. Obesity is a chronic, complex condition linked to increased risks of type 2 diabetes, cardiovascular disease and other health complications. Long-term management often requires sustained treatment alongside appropriate lifestyle and medical support. Viking’s oral formulation is intended to provide a convenient alternative to injectable therapies. A once-daily tablet could offer flexibility for patients and clinicians when considering treatment initiation and ongoing weight management. The company is also developing a subcutaneous formulation of VK2735, which is being evaluated in the separate VANQUISH Phase 3 program. The availability of oral and injectable formulations of the same investigational compound could potentially support different treatment preferences and management strategies. Nevertheless, whether the oral formulation delivers sufficient efficacy, tolerability and long-term benefit will depend on the results of the Phase 3 studies.
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Earlier Clinical Results Support Further Development
Viking’s decision to advance oral VK2735 into Phase 3 follows encouraging findings from the Phase 2 VENTURE-Oral Dosing study. In that study, participants receiving once-daily oral VK2735 experienced statistically significant, dose-dependent reductions in body weight over 13 weeks, with reductions of up to 12.2% from baseline. The company also reported that up to 97% of participants in certain treatment groups achieved at least 5% weight loss, while up to 80% achieved at least 10% weight loss. These findings were reported in the earlier Phase 2 setting and should not be interpreted as evidence of the results that will be achieved in the larger Phase 3 trials. The oral formulation demonstrated an encouraging tolerability profile in the Phase 2 study. Most reported drug-related treatment-emergent adverse events were mild or moderate, with gastrointestinal events among the most commonly observed effects. Such events are consistent with the known effects of GLP-1-based therapies and will remain important to monitor during further development. The SUNRISE studies will provide more extensive evidence on longer-term weight reduction, safety and tolerability across a larger population. Their results will help determine whether oral VK2735 can progress toward potential regulatory submission. For Viking Therapeutics, initiation of the SUNRISE program expands its clinical strategy in obesity and metabolic disease. The upcoming Phase 3 findings will be critical in determining the candidate’s potential role in future obesity treatment options.
Source: Viking Therapeutics press release
